The crypto driver provides a
device-independent framework to support cryptographic operations in
the kernel. The cryptodev driver provides userland
applications access to this support through the /dev/crypto
device. This node primarily operates in an ioctl(2) based model,
permitting a variety of applications to query device capabilities,
submit transactions, and get results.

If count given in
the specification, and is greater than 0, a maximum of one
crypto device is created.

The following ioctl(2)
calls apply only to the crypto devices:

CIOCGSESSION

Setup a new crypto
session for a new type of operation.

CIOCFSESSION

Free a previously
established session.

CIOCCRYPT

Perform a crypto
operation against a previously setup session.

FEATURES

Depending on hardware being present, the
following symmetric and asymmetric cryptographic features are
potentially available from /dev/crypto: